1. Field of the Invention
The invention is directed to a vibration damper with stroke-dependent damping force.
2. Description of the Related Art
A vibration damper with stroke-dependent damping force comprising a cylinder in which a displacer carries out a translational movement is known from U.S. Pat. No. 7,191,877 B2. The displacer has a work piston which divides the cylinder into two work spaces. The work spaces outside the displacer, for each operating movement direction of the displacer, are connected to damping valves by a flow connection. Every flow connection has only one flow direction through a check valve arrangement. The flow connection has a plurality of inflow ports which are offset in axial direction starting from the work spaces. A plurality of bypass channels form the flow connection for an operating movement of the displacer. An individual damping valve is arranged in each bypass channel. The example described with reference to FIG. 5 in U.S. Pat. No. 7,191,877 B2 comprises four bypass channels so that two damping valve can be used for each movement direction and, therefore, a maximum of three stroke-dependent damping force characteristics are available for each movement direction.
To achieve additional damping force characteristics, i.e., a more precisely stepped stroke-dependent damping force adjustment, another bypass channel must be provided. It can be seen from FIGS. 5 and 6 that there is no available installation space provided at the outer surface of the cylinder. Further, there is a smaller proportion of the surface area for cooling fins.